Scottish engineering giant Weir and financial services group abrdn are among those set to join the UK's largest quoted companies, making 2022 the biggest year for changes on London’s top index since the great financial crisis.

An analysis by wealth manager RBC Brewin Dolphin found there have been 12 changes to the FTSE 100 so far this year, the highest since 2009. This is set to rise to 15 when the next promotions and demotions take effect, making it the busiest since 2007 and 2008 when there were 19.

It would also be the second most active year during the past two decades, ahead of 2002 and 2006 when there were 14 changes.

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The two Scottish companies join Beazley in the upcoming round of promotions. Excluding the latest three promotions, there have been 228 additions and deletions from the FTSE 100 during the last 20 years.

Hikma Pharmaceuticals, Wood, and Tate & Lyle have been promoted and relegated the most times of any companies, with four promotions and four deletions each.

John Moore, senior investment manager at RBC Brewin Dolphin, said: “The amount of change to the FTSE 100 this year underlines how far the tide has gone out and how unloved many UK companies are – the level of M&A activity over the past 12 months is further proof of that.

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"Our recent meetings with smaller companies investment managers suggested they also expect the Numis Small Cap index to see its largest influx of mid-sized companies since 2008, highlighting this trend is almost universal."

Mr Moore added: “Weir is a great example of a company that has taken self-help measures to lift itself out of a potentially tricky position. It refocussed its business on mining and aggregates, moving away from its previous main market of oil and gas. At the same time, the company has truly engaged with its environmental impact and taken steps to improve its position on that front."

Weir exited the oil and gas sector in 2020 with the sale of its oil and gas division to Caterpillar in a deal with more than £300 million.